agreed...although I'm not familiar with the 2.7 tacomas...if it has 2 O2 sensors and you're getting a bank one lean code, then one of the two O2 sensors has failed. Bank one should be the one located closest to the engine if that ends up being the case. Good luck.

P.S. In the meantime, try disconnecting them both, that way it should fail rich, your gas mileage will suck, but at least you won't be toasting your slugs. <img src="/forums/images/graemlins/smile.gif" alt="" />

2007 Ford F150 Supercab